Sewing apparatus with contour cutting device



SEWING APPARATUS WITH coNToUR CUTTING DEVICE Filed July 25, 1966 K` NICOLAY April 9, 1968 4 Sheets-Sheet 1 INVENTOR: Kar/ NiCd/ay Attorney April 9 1968 K. NlcoLAY 3,376,836

SEWING APPARATUS WITH CONTOUR CUTTING DEVICE Filed July 25, 1966 4 Sheets-Sheet 2 IN VEN TOR.' KGF/ /V/co /dy BY 05, marl g K Attorney;

April ,9, 1968 K. NlcoLAY 3,376,836

SEWING APPARATUS WITH CONTOUR CUTTING DEVICE v Filed July 25,' 196e 4 sheets-sheet s INVENTR.' Kar/ /V/'co/dy Attorney April 9, 1968 K. NI'COLAY 3,376,836

SEWING APPARATUS WITH CONTOUR CUTTING DEVICE onoooaocooaoooonnconoaoooon r.

0ooaoooooooooao VMM fnvenf'or.- /far/ Nico/oy By" :Karl RgSSAttorney United States Patent Oiice 3,376,836 Patented Apr. 9, 1968 D 4 1 Claims. (Cl. 112-124) My present invention relates to automatic sewing-machine arrangements provided with cutting devices for severing the fabric along an edge parallel to and during the formf'ation of a stitching line conforming to the cut edge.

It has been proposed heretofore to provide temfplatecontrolled sewing machines vfor for-ming a stitch line Ialong the border of a pocket, a collar, a seam or a hem with cutting means for forming a cut edge whose contours are parallel to the stitched seam and which conforms to the outlines thereof. In such devices, the template controls -t-he feed of the fabric so that the advance thereof with respect to the stitching location always takes place in the same direction, usually that of the sewing operation.

With such devices, the cutting of the fabric parallel to the stitch line is no problem inasmuch as the blades of the cutting means need only be oriented in the direction of fabric feed. Devices of this type, however, are rather slow, complex, diicult to handle and relatively expensive.

In order to overcome the disadvantages of such complex camming systems, it has been the practice to provide automatic sewing machine systems with template assemblies mounted mounted for movement along two coordinates (eg. via rails or other co-ordinate-resolving systems). Such arrangements could not hitherto be effectively `used yfor the simultaneous severing of the fabric parallel to the seam line without increasing the complexity of the cam means and'encountering difficulties arising from the substantial forces needed to operate a cutting device where multidirectional movements arise.

It is the principal object of this invention to provide -a combination cutting and stitching arrangement with template control whereby these disadvanages can be obviated.

I have found that this object and others which will be apparent hereinafter, can be attained when an automatic sewing machine having a template assembly for movement in at least two mutually perpendicular directions or with two mutually perpendicular components relative to the stitching location is provided with sensing means responsive 'to the change of direction of the fabric feed for swinging the cutting device about the stitching location or an axis corresponding to the needle axis via a mechanical torque amplifier permitting orientation of the cutting device corresponding to the contours of the template without any strain upon the sensing means.

According to a more specific feature of this invention, the torque amplified and the template-shifting means have ia common drive while the torque amplifier is provided with a shaft through the interior of which the drive shaft or the template-feed means passes. T-he latter preferably carries a start or pinion wheel engageafble with a rack `formation carried by the template assembly alongside a groove conforming to the contours to be stitched and cut. The star-wheel shaft is received in this groove and is flanked :by a pair of pins constituting the sensing means and carried by a slide which is radially shiftable in a rotiary body rigid `with the amplifier sha-ft.

The above and other objects, features and advantages of the -present invention will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

FIG. 1 is an elevational view, partly broken -away and partially in diagrammatic form of a pattern-controlled garment feed automatic sewing machine having edgecutting means in accordance with the present invention;

FIG. 2 is a cross-sectional View of a drive mechanism drawn to an enlarged scale, for the pattern-carrying means and illustrating the mechanism connecting it with the actuating system for the cutting device;

FIG. 3 is a front-elevational view of the machine with the cutting device illustrated partly in section;

F'IG. 4 is a plan View of the pattern template and fabric-feed arrangement, drawn to an enlarged scale; and

FIG. 5 is a cross-sectional view taken along the line V-V of FIG. 2.

General description As illustrated in the `drawing and particularly FIG. l, a template-'controlled automatic sewing machine 1 can be provided with a post 1a in the usual manner upon la support 1b formed with the fabric-receiving table 28. The arm 1c of this automatic sewing machine, which is itself conventional, carries the head 1d in which the needle assembly N is reciproca'ble and which overhangs the table 28 Wh'ile being positioned over the stitching location S. The automatic sewing machine of FIG. l can be of the type used for stitching pocket aps, collars, and the like. In the region of the stitching location S, a clamping and stretching device 2 is provided for holding the fabric workpiece against the table and movably clamping it for displacement through the stitching operation. The clamping and stretching foot 2 (FIG. 4) is described in greater detail hereinafter although it must be noted that it is connected with the pattern template 3 for joint movement. The pattern template 3 is shifted by a drive mechanism, described further below, upon a co-ordinate system formed by a pair of mutually perpendicular guides =87. The co-ordinfate system and its entrainment ofthe pattern template 3 is so arranged that the direction of advance of the fabric-clamping member 2, with reference to the stitching location S, and consequently the movement of the fabric changes from time to time with components along each co-ordinate or movements along one co-ordin-ate followed by movements Ialong the other.

F abric-cutting mechanism As indicated earlier, the apparatus is provided with an edge-cutting apparatus K designed to sever the fabric workpiece parallel to the stitch line in spite of the twoco-ordinate movement of the fabric and its clamping foot. The cutting device K is, Iaccording to an important feature of the present invention, swingably mounted upon a vertical axis passing through the stitching location Sand thus conforming approximately to the needle axis of the sewing machine 1. The swinging movement of the cutting device is synchronized with the movement of the patterning template 3 by means ofa motion-translating mechanism whose feeler or sensing element engages the camming curve or groove 3 of the pattern template 3 and actuates the rotating mechanism for the cutting device disposed adjacent the stitching location S via a torque amplifier V (FIG. 2).

The edge-cutting device K comprises a movable blade 7 whose cutting portion 7a projects through the fabric F (FIG. 2) adjacent the stitching location and at right angles to the shank 7b of this blade. Thus the cutting portion 7a underlies the fabric and co-operates with a xed blade 8 above the fabric with a scissor action which forms the cut at the edge as required. The fixed blade 8 and the cutting portion 7a of the movable blade 7 converge in the direction of fabric feed (arrow 7c) past the cutting device.

Both blades 7 and 8 are received in a groove 11 (FIG. 5) running parallel to the needle axis (i.e. vertically) in a vertical arm 12' (FIG. 3) of a support body 12 swingable labout the needle axis. The needle is here shown at N and is carried by the usual needle shaft. The fixed blade 8 is fastened to the oor of the groove 11 by means of screws permitting adjustment of the distance between the blade 8 and the cutting portion 7a corresponding to the thickness of the fabric F in the open condition of the blade means. The movable blade 7 is affixed Hush to the stationary blade 8 and is secured to a spring plate 13 mounted on the arm 12 by means of screws 13' so that the blade 7 is springloaded against the fixed blade 8 and slides in the groove 11 parallel to the needle movement through an upstroke and a downstroke.

Cutter-recprocaton drive The vertical reciprocating blade 7 is driven by a motor 14 mounted upon the arm 1c via a pedestal 14a and having a drive wheel 14' connected by a V-belt to the driven wheel 14b journaled in a bearing 15 located above the head 1d of the sewing machine. The pulley 14b, which is connected with the drive pulley 14 via the V-belt 14e, is keyed to a crankshaft 16 whose eccentric stub 16a is rotatable in a further bearing 17 slidable within a groove 1S of a bushing 19 clamped around the upper end of a shaft 20. The latter passes vertically through the head 1d of the sewing machine in a slide-bearing guide 20a and emerges below the head at 2Gb. Thus the reciprocating shaft 20 moves parallel to the needle N and its actuating rod N which is coupled in the usual manner to a hand wheel 1e and the customary needle drive. At this lower end 2012 of the rod 20, I clamp a further ring 21 which has a circular flange 21' whose center of curvature coincides with the needle axis and which permits the blade 7 to be swung about this axis via a rotating mechanism connected with the fiange 21' via a hook-shaped portion 22.

This swinging movement of the cutting means 7, 8 to follow the contours of the pattern template 3 and the camming curve 3' is effected via a pair of sensing pins 4 which project through the groove 3 in the template 3 and which are connected with the torque amplifier V (FIGS. 1 and 2) to increase the sensed torsional increment and apply the resultant force to the cutting system.

Template drive The pattern template 3 is driven via a pin-type rack arrangement which co-operates with a star wheel or pinion as illustrated in FIGS. 3 and 4. Thus the camming groove 3' is flanked by a row of pins 25 which project upwardly from the template 3 and are spaced apart along the groove and parallel thereto to form a pin rack. The pinion is constituted by a star wheel 26 in mesh with the pins and carried by a shaft 27 which passes through the table 28 and is also rotatably received in the groove 3 to guide the template while displacing it. The wheel 26 is driven by a motor (not shown) via -a belt transmission including the V-belt 29 and a driven pulley 30a (FIG. 2) engaged thereby. The driven pulley 30a is keyed to a vertical shaft 30 journaled in a frame 32 via bearings 31 and 31'. The frame 32 is mounted via bolts 36 and nuts 36a upon the table 28 via spacing sleeve 37. The torque amplifier V is mounted in the frame 32 which comprises an upper plate 33 and a lower plate 34 connected by tie bolts 35.

Torque amplifier The transfer of rotary movement sensed by the pins 4 is effected via the torque amplifier V received between the plates 33 and 34 of the frame as indicated earlier. The

main vertical shaft 39 of this amplier is tubular and coaxially receives the shaft 27 of star Wheel 26. The shaft 39 is supported against downward movement by a thrust collar 38. The transfer of rotary motion from the shaft 30 to the shaft 27 is effected via an overloading slip-type clutch 41. Thus the shaft 30 has affixed thereto a gear 42 which meshes with the gear 43 rotatably mounted on a shaft 44'. The clutch portion 44 of shaft 44' is journaled in a bore of the bearing sleeve 45 which is clamped via a flange 45 and its counternut 46 against the plate 34 of the frame 32 so that the sleeve 45 is coaxial with the main shaft 39. The shaft 44, which is keyed to the shaft 27 of the pin wheel 26, is provided in its clutch portion 44 with an axial slot 44" into which the projections 47" of a pair of friction-drive disks 47 nad 47' engage. The disks 47 and 47', which may be provided on their frictional faces with clutch-lining material or the like, flank the driven gear 43. The axially movable assembly constituted by the disks 47, 47' and the driven gear 43 is positioned by means of a coil spring 48 seated against a nut 49 at the bottom end of the shaft 44. The coil spring 48 bears axially against the clutch disk 47 which, in turn, bears axially against the gear 43 and urges the latter against the disk 47 and the bushing 45. The clutch pressure is controlled by the nut 49 and the degree of prestressing of the coil spring 48. It will be understood that rotation of shaft 30 by the respective motor and belt drive 29, 36a, will transfer this rotation to the gear 43 and, via the clutch disks 47 and 47', to the shaft 27 and the pin Wheel 26. The template 3 will, accordingly, be advanced at the rate of rotation of the pin wheel. If a blockage of the movement of the template or some other overloading occurs, the disks 47 and 47' will slip relative to the gear 43 and prevent breakage. The shaft 27 has its lower end projecting into a bore 50 of corresponding noncircular cross section to ensure transfer of movement from the shaft 40" to the shaft 27.

The transfer of torque to the blade means 7, 8 is effected in the torque amplifier V by means of friction band clutches illustrated at 61 and 62 and respectively operative upon rotation of the shaft 39 in the counterclockwise and clockwise senses. The main shaft 39 is journaled at the upper end in a bushing 57 against which the thrust collar 38 bears axially. The upper flange 58a of this bushing rests upon the plate 33 while a roller bearing 58 is provided at the lower end of shaft 39 for rotatably holding it within the bushing 45. The roller bearing 5S is held axially by a ring 59.

Friction-band clutch means The friction-band clutch 61 carries a gear 64 which is freely rotatable upon the shaft 39 and is held against the bushing 57. This gear meshes with a gear and thus tends to be driven in the counterclockwise sense. The symmetrically arranged friction band clutch 62 has a corresponding free-running sprocket wheel which is driven from the sprocket wheel v-56 via a chain drive `56a in the clockwise sense. The driving gear 55 and the driving sprocket 56 are rotatably entrained with the shaft 30 via respective setscrews. Between the freewheeling gear 64 and the freewheeling sprocket `wheel 65, the main shaft 39 is formed with a spacing ring 63.

A clutch member 66, having an annular central portion 66', is located between the freewheeling gear 64 and the freewheeling sprocket 65 and serves as an anchor for a friction band in the form of a torsion spring 69, extending from the annulus 66 to the gear 64 and the sprocket A65, respectively. The upper and lower portions 69 and 70 of this helically wound friction band surround the sleeve portions of gear 64 and sprocket 65 as well as the spacer ring 63 separating these sleeve portions. A screw I68 connects the clutch member 66 with the main shaft y39 so that, upon rotation of member 66, the main shaft 39 is rotated in the corresponding sense. The torsion-spring friction bands 69 and 70 are connected at their free ends with gears 71 and 72, respectively, which are journaled upon the sleeves of gear 54 and sprocket 65.

When, upon rotation of the main shaft 39, one or the other of the torsion springs 69 and 70 tightly hug the respective bushing 64 or 65, the respective gear 71 or 72 is entrained and the rotary movement transferred to the driven gear 78 or 79. These latter gears are rigid with the intermediate shaft 75 which is journaled in bearing 73 and 74 of the frame, parallel to the main shaft 39.

Belt-transmission means On its upper end, the shaft 75 is keyed to a wheel 23 with a milled periphery which is engaged by a `belt 23 of a nonslip belt drive (FIGS. 1 and 2). The belt drive 23, 23 transforms the angular oscillations of the shaft 39, to which the block 81 carrying pins 4, is secured, into the rotation of a shaft 76. As illustrated in FIG. 1, the shaft 76 is journaled in the table 28 and has an extremity projecting therebelow and carrying a driven pulley 23 about which the lbelt 23 passes. The shaft 76 is coupled with a y further shaft 77, rotatably mounted in a bearing 82', via a releasable shaft linkage 82, t-hev shaft 7-7 -being further provided with a pulley 24" whose belt 24 passes therearound and about the wheel 24 serving to twist the support 12 for the blade means. The wheel 24 of the belt drive 24, 24', 2'4", is fastened to the horizontally extending arm 12" of the body 12 carrying the yblade means and rotatable about the needle axis; the screw ('FIGS. 2 and 5) affixes the arm 12" to the ring 24.

@Both friction band clutches 61 and 62 receive respective impulses from the main shaft 39 upon rotation of the body 81 whose pins 4 follow the curvature of the groove 3. The pins 4 are carried by a slide 80 (FIGS. 2 and 4) surrounding the shaft 27 and slidably received in a groove at the upper end of the body 81.

Operation After a fabric F of the usual type is clamped by the stretching foot 2 in working position (via a conventional linkage 2a), the template assembly M consisting of the stretching foot 2 and the pattern template 3 is placed upon the table 28 with the shaft 27 passing through the groove 3 and the star wheel 26 in engagement with the pins 25. The rollers 5 of the template assembly M (FIGS. 1, 2 and 4) are guided in the rail 85 which has arms 85 passing through slots 87 of the table 2S and engaging a pair fo links 86 below the table 28. The links 86 guide the rail 85 for movement parallel to itself so that the rail 85 and the slots 87 form mutually perpendicular co-ordinate movement means of the character mentioned above. The

template assembly M is so arranged that the star wheel 26 l initially engages the starting portion 3" (FIG. 4) and thus commences its meshing engagement with the rack formed of pins 25. Referring again to FIG. 4, it is evident that initial rotation of the star wheel will shift the template assembly M upon the co-ordinate system 8S-87 from right to left during the bight of the loop-shaped stitch while the arms of the stitching configuration correspond to movement in the vertical direction of FIG. 4. Thus the overall -movement of the template assembly M will have a main component in the direction of the X-axis of the co-ordinate system whereas movement of the template system M in the vertical direction of FIG. 4 will correspond to a secondary component along the Y-axis.

The motor of the belt-drive 29, 30, etc. is provided with a limit switch 88 (FIGS. 2 and 4) engaged by an edge 89 of the template assembly M, this switch serving to energize the motor of belt drive 29 to begin the feed of fabric F. When another edge 90 at the other side of the template assembly M engages the limit switch 88, t-he drive for the wheel 27 is rendered inoperative.

To ensure that the pins 4 will be in the same orientation with reference to the stitching location S at the beginning and end of each cycle and thus ensure that there will be no difficulties in inserting the template assembly M so that the pins properly enter the groove 3, it has been found to be advantageous to provide the curvature 3' of the outlet portion of the groove identical in configuration and orientation to the inlet portion 3". As the groove 3 with its varying contours is swept past the shaft 27, the angular orientation of the pins 4, the slider and the -body 81 change in accordance with the coordinate movements of the -template assembly. Rotation of the shaft 39 in one or the other sense results in an amplified transmission of torque via the friction band 69 (counterclockwise rotation of shaft 39) or the friction band 70 (clockwise rotation of the shaft 39). It will lbe seen that in thestationary condition of shaft 39, neither of the torsion bands 69, 70 is stressed against the respective sleeve 64 or 65 so that both freewheel upon the shaft 39. When the shaft 39 is rotated slightly, however, the respective band 69 or 70 embraces the sleeve 64 or 65 and frictionally entrains i-t in the respective direction so that motion is transmitted to the corresponding gear 71 or 72 and thence `via belt drives 23, 23', 23 and 24, 24', 24" to the :blade means 7 and 8. The actual torque applied is .that derived from the rotary movement transferred between the shaft 30 and the shaft 75 via one of the gear seats 71, 78 or 72, 79. The pins 4 need only sense the changing contours of the groove 3' and operate Without any substantial pressure while generating, via the torque amplifier V, sufficient force to twist the cutting blades 7 and 8 during the severing operation and while -they engage the fabric. Substantially no load is applied to the pin wheel 26, the pins 25 or the drive system therefor. Only a single cam of light construction is required for the stitching and cutting operation even when a multiplicity of layers must -be cut simultaneously and stitched together.

The invention described and illustrated is believed to admit of many modifications within the ability of persons skilled in the art, all such modifications being considered within the spirit and scope of the appended claims.

I claim:

1. In a sewing machine for the stitching of seam lines on a fabric and having a stitching arm overhanging a table and a stitching needle reciprocable in said arm toward and away from said table, the improvement which comprises in combination:

(a) a template assembly on said table entraining said fabric for displacing the same relative to said needle and a stitching location on said table in accordance with a predetermined pattern on the template of said assembly;

(b) coordinate guide means carried by said table and engaging said template assembly for resolving the movement of said template assembly into two mutually perpendicular components;

(c) cutting means in the region of said stitching location including blade means engageable with said fabric, and means mounting said cutting means for swinging movement about the axis of said needle;

(d) drive means for shifting said template assembly along said predetermined pattern on said template to pass said fabric through said stitching location in a pattern corresponding to said contour;

(e) sensing means responsive to said contour and angularly displaceable in accordance with changes in said contour;

(f) torque-amplifier means lbetween said sensing means and said cutting means for transmitting rotary increments of said sensing means to said cutting means, said sensing means being substantially free of stress during transmission of said rotary increments to said cutting means.

2. The combination defined in claim 1 wherein said torque-amplifier means and said drive means have a common source of motive power.

3. The combination defined in claim 2 wherein said predetermined pattern is defined by a groove formed in said template assembly and said drive means includes rack means on said -template assembly extending alongside said groove and pinion means meshing with said rack, said torque-amplifier means having a main shaft extending perpendicularly to said table, said pinion means having a shaft passing coaxially through said main shaft of said torque-amplier means.

4. The combination defined in claim 3 wherein said sensing means includes a pin received in said groove alongside said pinion means, a slider carrying said pin, and a rotary body connected with said main shaft and slidably receiving said slider.

5. The combination defined in claim 4 wherein said shafts depend from said table, said torque-amplifier means comprising an input shaft driven by said source of motive power, a pair of sleeves freely rotatable upon said main shaft and axially spaced therealong, respective transmission means connecting said sleeves with said input shaft for rotation of said sleeves in opposite directions, and

respective clutch means on said main shaft actuatable upon rotation thereof in opposite directions for entraining a respective one of said sleeves in the corresponding direction.

6. The combination defined in claim 5 wherein said torque-amplifier means further comprises an output shaft, a belt transmission coupling said output shaft with said cutting means, a pair of driven gears connected to and axially spaced along said output shaft, and a respective drive gear connected with each of said clutch means and meshing with a respective one of said driven gears on said output shaft.

7. The combination defined in claim 6 wherein each of said clutch means includes a friction band helically wound about the respective sleeve and connected to the respective drive gear.

5 8. The combination defined in claim 7 wherein said cutting means includes a vertically reciprocable bar carried 'by said head, motor means on said head for vertically displacing said bar, a ring affixed to a lower end of said bar and surrounding the needle axis, and a driven Wheel rotatable by said beit transmission and carried by said ring and being affixed to said blade means.

9. The combination defined in claim 8 wherein said blade means includes a vertically shiftable blade having a cut-ting portion underlying said fabric and a fixed blade disposed above said fabric.

10. The combination defined in claim 7 wherein said coordinate guide means includes a guide rail carrying said template assembly and a pair of links hinged to said guide rail and underlying said table for constraining said guide rail to movement parallel to itself.

References Cited UNITED STATES PATENTS 688,961 12/1901 McDonald 112-2 1,197,112 9/1916 Eberley 112-2 2,142,476 1/ 1939 McDonald 117/-2 3,001,489 9/1961 Bond et al. 112-2 3,332,378 7/1967 Adam et al. 112-2 JORDAN FRANKLIN, Primary Examiner.

H. HAMPTON HUNTER, Examiner. 

1. IN A SEWING MACHINE FOR THE STITCHING OF SEAM LINES ON A FABRIC AND HAVING A STITCHING ARM OVERHANGING A TABLE AND A STITCHING NEEDLE RECIPROCABLE IN SAID ARM TOWARD AND AWAY FROM SAID TABLE, THE IMPROVEMENT WHICH COMPRISES IN COMBINATION: (A) A TEMPLATE ASSEMBLY ON SAID TABLE ENTRAINING SAID FABRIC FOR DISPLACING THE SAME RELATIVE TO SAID NEEDLE AND A STITCHING LOCATION ON SAID TABLE IN ACCORDANCE WITH A PREDETERMINED PATTERN ON THE TEMPLATE OF SAID ASSEMBLY; (B) COORDINATE GUIDE MEANS CARRIED BY SAID TABLE AND ENGAGING SAID TEMPLATE ASSEMBLY FOR RESOLVING THE MOVEMENT OF SAID TEMPLATE ASSEMBLY INTO TWO MUTUALLY PERPENDICULAR COMPONENTS; (C) CUTTING MEANS IN THE REGION OF SAID STITCHING LOCATION INCLUDING BLADE MEANS ENGAGEABLE WITH SAID FABRIC, AND MEANS MOUNTING SAID CUTTING MEANS FOR SWINGING MOVEMENT ABOUT THE AXIS OF SAID NEEDLE; (D) DRIVE MEANS FOR SHIFTING SAID TEMPLATE ASSEMBLY ALONG SAID PREDETERMINED PATTERN ON SAID TEMPLATE TO PASS SAID FABRIC THROUGH SAID STITCHING LOCATION IN A PATTERN CORRESPONDING TO SAID CONTOUR; (E) SENSING MEANS RESPONSIVE TO SAID CONTOUR AND ANGULARLY DISPLACEABLE IN ACCORDANCE WITH CHANGES IN SAID CONTOUR; (F) TORQUE-AMPLIFIER MEANS BETWEEN SAID SENSING MEANS AND SAID CUTTING MEANS FOR TRANSMITTING ROTARY INCREMENTS OF SAID SENSING MEANS TO SAID CUTTING MEANS, SAID SENSING MEANS BEING SUBSTANTIALLY FREE OF STRESS DURING TRANSMISSION OF SAID ROTARY INCREMENTS TO SAID CUTTING MEANS. 